Polyanilines and methods thereof

ABSTRACT

The present disclosure provides polyanilines, articles thereof, and methods of forming polyanilines. In at least one aspect, a polyaniline has a thermal stability of about 100° C. or greater, a weight average molecular weight (Mw) of from about 50,000 g/mol to about 150,000 g/mol and a molecular weight distribution (Mw/Mn) of from about 1 to about 5. In at least one aspect, a film includes a polyaniline, the film having a hydrocarbon content of about 1 wt % or less, based on the total weight of the film. In at least one aspect, a method includes introducing an emulsion of an aqueous solution of an aniline and an alkyl-substituted aryl sulfonic acid having 1 wt % or less of hydrocarbon content into a flow reactor, the flow reactor having a length of tubing having an inner diameter. The method includes polymerizing the monomer within the tube to form a polyaniline.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit of and priority to co-pending U.S.Provisional Application Ser. No. 62/832,143 filed on Apr. 10, 2019,which is hereby incorporated by reference in its entirety.

FIELD

The present disclosure provides polyanilines, articles thereof, andmethods of forming polyanilines.

BACKGROUND

By appropriate design of the chemical structure, conjugated polymericmaterials can be used as additives providing anti-corrosive andanti-static properties or employed in electronic applications such asorganic light-emitting diodes (OLED), solar cells, semiconductors,display screens and chemical sensors. Conjugated polymeric materials,however, typically suffer from high manufacturing costs, materialinconsistencies and processing difficulties when prepared by batchprocesses.

Despite these advances, using current methods there are limitations tothe expanded use of conductive polymers. For example, polyaniline (PANIor “emeraldine”) is one such conductive polymer that, due to highmanufacturing costs, material inconsistencies and batch processingdifficulties, is not fully exploited. PANI is widely used in printedboard manufacturing as a final finish; protecting the copper andsoldered circuits from corrosion. PANI is commonly prepared by chemicaloxidative polymerization of aniline in an aqueous solution. Materialobtained by this approach is amorphous and insoluble in most organicsolvents. Furthermore, conventional PANI products typically do not haveas high of a thermal stability as would be otherwise desired. Inaddition, to form PANI, many of the current flow reactors underevaluation use microfluidic chips or miniaturized columns andspecialized equipment for control of the flow devices that adds cost andcomplexity to the process.

There is a need for new and improved polyanilines, articles havingpolyanilines, and methods for forming polyanilines.

SUMMARY

The present disclosure provides polyanilines, articles thereof, andmethods of forming polyanilines.

In at least one aspect, a polyaniline has a thermal stability of about100° C. or greater, a weight average molecular weight (Mw) of from about50,000 g/mol to about 150,000 g/mol and a molecular weight distribution(Mw/Mn) of from about 1 to about 5.

In at least one aspect, a film includes a polyaniline, the film having ahydrocarbon content of about 1 wt % or less, based on the total weightof the film.

In at least one aspect, a method includes introducing an emulsion of anaqueous solution of an aniline and an alkyl-substituted aryl sulfonicacid having 1 wt % or less of hydrocarbon content into a flow reactor,the flow reactor having a length of tubing having an inner diameter. Themethod includes polymerizing the monomer within the tube to form apolyaniline.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the presentdisclosure can be understood in detail, a more particular description ofthe disclosure, briefly summarized above, may be had by reference toexamples, some of which are illustrated in the appended drawings. It isto be noted, however, that the appended drawings illustrate only typicalexamples of this present disclosure and are therefore not to beconsidered limiting of its scope, for the present disclosure may admitto other equally effective examples.

FIG. 1A is a diagram of an exemplary flow reactor system, according toone or more aspects.

FIG. 1B is a diagram of an exemplary series flow reactor system,according to one or more aspects.

FIG. 1C is a diagram of an exemplary parallel flow reactor system,according to one or more aspects.

FIG. 2 is a process flow diagram of a polymerization method using thesystem and methods, according to one or more aspects.

FIG. 3 is a cross-sectional view of the flow reactor inner diameterarea, according to one or more aspects.

FIG. 4 is a cross-sectional view of the flow reactor inner diameter areawith conductive polymer reaction product occupying a portion of theinner diameter area, according to one or more aspects.

FIG. 5 is a process flow diagram of a polymerization method using thesystem and methods, according to one or more aspects.

FIG. 6 is a process flow diagram of a polymerization method ofPANI-DNNSA using the system and methods, according to one or moreaspects.

FIG. 7A is a graph illustrating gel permeation results (refractive indexvs. retention volume (mL)) using a refractive index detector ofpolyanilines, according to one or more aspects.

FIG. 7B is a graph illustrating gel permeation results (viscometerdifferential pressure vs. retention volume (mL)) using a viscometer ofpolyanilines, according to one or more aspects.

FIG. 8 is a graph illustrating thermal stability data (resistance vs.temperature) of polyanilines, according to one or more aspects.

FIG. 9 is a graph illustrating thermal stability data (resistance vs.temperature) of polyanilines, according to one or more aspects.

FIG. 10a is overlaid FTIR spectra of DNNSA, according to one or moreaspects.

FIG. 10b is overlaid FTIR spectra of DNNSA, according to one or moreaspects.

To facilitate understanding, identical reference numerals have beenused, where possible, to designate identical elements that are common tothe figures. It is contemplated that elements and features of oneexample may be beneficially incorporated in other examples withoutfurther recitation.

DETAILED DESCRIPTION

The present disclosure provides polyanilines, articles thereof, andmethods of forming polyanilines. Polyanilines of the present disclosurecan be substantially free of byproducts such as un-sulfonatedhydrocarbons which provides reduced “outgassing” of the polyanilines ascompared to conventional polyanilines. Polyanilines of the presentdisclosure can have a thermal stability of about 100° C. or greater, aweight average molecular weight (Mw) of from about 50,000 g/mol to about150,000 g/mol, and/or a molecular weight distribution (MWD) of fromabout 1 to about 5. Reduced outgassing and improved molecular weightproperties of polyanilines of the present disclosure provide improvedthermal stability, as compared to conventional polyanilines.

Methods of the present disclosure include forming polyanilines of thepresent disclosure by using an aniline and an alkyl-substituted arylsulfonic acid (such as dinonylnaphthylenesulfonic acid (DNNSA)). Thealkyl-substituted aryl sulfonic acid of methods of the presentdisclosure has 1 wt % or less of un-sulfonated hydrocarbon content.Conventional alkyl-substituted aryl sulfonic acids (such as DNNSA) havegreater than 1 wt % of un-sulfonated hydrocarbon content. Un-sulfonatedhydrocarbons can include branched and linear paraffins and/or aromatics(such as benzene and naphthalene). It was hypothesized that theun-sulfonated hydrocarbon content of, for example, conventional DNNSAsamples was provided by decomposition of the sulfonic acid when placedunder ultra-high vacuum for storage. However, it has been discoveredthat the un-sulfonated hydrocarbons are already present in the DNNSAsamples and are likely byproducts of production of conventional DNNSAmanufacturing processes. Use of, for example, DNNSA having 1 wt % orless of unsulfonated hydrocarbon content can provide polyanilines havingreduced outgassing and improved thermal stability. Polyanilines andarticles thereof having reduced outgassing and improved thermalstabiltity can provide compositions, coatings, layers, etc. for use in awide range of articles, such as aircraft, landcraft, wind turbines,satellites, etc.

Polyanlines

Polyanilines of the present disclosure can be an acidified polyaniline(hereinafter referred to as a PANI-Acid or an “emeraldine salt”) or aneutral polyaniline. Acidified forms of polyaniline can haveconjugate-base counterions (as anionic ligands), as described in moredetail below. Neutral polyanilines can be formed by neutralizing aPANI-Acid under any suitable conditions, such as by treating thePANI-Acid with a sodium hydroxide solution and washing the neutralizedpolymer product with water.

Molecular weight data herein (Mw, Mn, Mz, Mp, and Mw/Mn) refer toneutral polyaniline (e.g., un-charged; un-doped forms of thepolyaniline). In other words, molecular weight of polyanilines herein donot include the molecular weight added by the presence of a dopant, suchas an acid, such as DNNSA.

Polyanilines of the present disclosure can have a weight averagemolecular weight (Mw) of from about 50,000 g/mol to about 150,000 g/mol,such as from about 75,000 g/mol to about 100,000 g/mol, alternativelyfrom about 100,000 g/mol to about 130,000 g/mol. Polyanilines of thepresent disclosure can have a number average molecular weight (Mn) offrom about 50,000 g/mol to about 100,000 g/mol, such as from about60,000 g/mol to about 80,000 g/mol, alternatively from about 80,000g/mol to about 100,000 g/mol.

Polyanilines of the present disclosure can have a molecular weightdistribution (MWD) of from about 1 to about 5, such as from about 1 toabout 4, such as from about 1 to about 3, such as from about 1.2 toabout 2.5, such as from about 1.3 to about 1.7, as determined by gelpermeation chromatography. MWD is determined by dividing Mw by Mn andcan be referred to herein as “Mw/Mn”.

Polyanilines of the present disclosure can have a z-average molecularweight (Mz) of from about 75,000 g/mol to about 250,000 g/mol, such asfrom about 100,000 g/mol to about 250,000 g/mol, such as from about150,000 g/mol to about 250,000 g/mol. Mz is indicative of high molecularcontent of a polymer. For example, Mz values of polyanilines of thepresent disclosure can be higher than Mz values of conventionalpolyanilines, which can provide improved processability as compared toconventional polyanilines.

Polyanilines of the present disclosure can have a peak average molecularweight (Mp) of from about 50,000 g/mol to about 150,000 g/mol, such asfrom about 100,000 g/mol to about 150,000 g/mol, such as from about110,000 g/mol to about 140,000 g/mol, such as about 113,000 g/mol toabout 136,000 g/mol. Peak average molecular weight is indicative of themode of the molecular weight of polymer distribution, highlighting theincreased molecular weight of polyanilines of the present disclosure.

Molecular weight properties (such as Mw, Mn, Mz, Mp) of polyanilines canbe determined using Gel Permeation Chromatography. The mobile phase canbe 0.02 M ammonium formate (AF) in N-methylpyrrolidone (NMP). Theuniversal calibration technique can be used to measure molecular weightdistributions utilizing viscometric and refractive index detectors. Thesolutions can be filtered through a 0.45 micron filter prior to use. Thepolyaniline samples can be precipitated in spectroquality methanol,washed four times with methanol and recovered using vacuum filtration.The samples can be air dried, dissolved in AF-NMP, and passed through a0.2 micron filter directly into GPC vials for analysis.

An article, e.g. a film, of polyaniline of the present disclosure canhave a hydrocarbon content of about 1 wt % or less, such as about 0.5 wt% or less, such as about 0.1 wt % or less, such as from about 0.001 wt %to about 1 wt %, such as from about 0.01 wt % to about 0.5 wt %, basedon the total weight of the sample (e.g., film). For example, a film canhave a hydrocarbon content of about 1 wt % or less, based on the totalweight of the film, e.g., the total weight of hydrocarbon content,polyaniline, and dopant. Hydrocarbons include C1-C20 paraffins andaromatic hydrocarbons such as benzene and naphthalene. In at least oneaspect, a hydrocarbon is naphthalene.

An article, e.g. a film, of polyaniline of the present disclosure canhave an outgassing % of about 0.5% or less, such as about 0.3% or less,such as about 0.1% or less, such as about 0.05% or less, such as about0.01% or less, according to ASTM E595-93.

Polyanilines of the present disclosure can have a thermal stability ofabout 100° C. or greater, such as about 110° C. or greater, such asabout 120° C. or greater, such as from about 120° C. to about 160° C.,such as from about 130° C. to about 160° C., such as from about 140° C.to about 160° C., such as from about 150° C. to about 160° C. Thermalstability can be determined by spin coating a polyaniline onto amicroscope slide and drying the spin coated sample at 70° C. Silver barscan be painted on the edges of slide for electrical contacts. Samplescan be exposed to a temperature (e.g., 150° C.) for 24 hours in aconvection oven. Then, the resistance of the sample can be measured todetermine thermal stability.

In at least one aspect, a polyaniline is a PANI-Acid represented byFormula (I):

where each instance of R¹, R², R³, and R⁴ is independently selected fromhydrogen, substituted or unsubstituted C1-C20 alkyl, substituted orunsubstituted C1-C20 aryl, substituted or unsubstituted C1-C20 alkaryl,substituted or unsubstituted C1-C20 arlyalkyl, substituted orunsubstituted C1-C20 alkoxyl, and halogen (such as fluoro, chloro,bromo, or iodo), wherein one or more instances of R¹, R², R³, and R⁴ areoptionally substituted with a group independently selected from C1-C20alkxoyl and halogen (such as fluoro, chloro, bromo, or iodo);each instance of A⁻ is an anionic ligand;n is an integer such that the weight average molecular weight (Mw) ofthe polyaniline is from about 55,000 g/mol to about 80,000 g/mol, suchas from about 60,000 g/mol to about 75,000 g/mol, such as from about65,000 g/mol to about 70,000 g/mol.

In at least one aspect, each instance of R¹, R², R³, and R⁴ isindependently selected from hydrogen and unsubstituted C1-C20 alkyl. Inone or more aspects, C1-C20 alkyl is selected from methyl, ethyl,propyl, n-butyl, iso-butyl, sec-butyl, n-pentyl, iso-pentyl, sec-pentyl,n-hexyl, iso-hexyl, and sec-hexyl. In at least one aspect, each instanceof R¹, R², R³, and R⁴ is hydrogen.

In at least one aspect, C1-C20 aryl is selected from phenyl andnaphthyl. In at least one aspect, C1-C20 alkaryl is benzyl. In at leastone aspect, C1-C20 arlyalkyl is toluyl, mesityl, or ethylbenzyl.

In at least one aspect, each instance of A⁻ is an anionic ligandindependently selected from a sulfonate, a hydroxide, and a halogen(such as fluoro, chloro, bromo, or iodo). In one or more aspects, A⁻ isa sulfonate such as a dinonylnaphthalene sulfonate.

Alkyl-Substituted Aryl Sulfonic Acids, Anilines, and Methods forPreparing Polyanilines

A representative non-limiting reaction scheme for forming polyanilinesof the present disclosure is shown below in Scheme 1. As shown in Scheme1, an aniline is treated with an alkyl-substituted aryl sulfonic acidand a catalyst to form a polyaniline represented by Formula (I).

R¹, R², R³, R⁴ and A⁻ of Formula (I) of Scheme 1 are as described forFormula (I) above.

For the aniline monomer of Scheme 1, each instance of R¹, R², R³, and R⁴is independently selected from hydrogen, substituted or unsubstitutedC1-C20 alkyl, substituted or unsubstituted C1-C20 aryl, substituted orunsubstituted C1-C20 alkaryl, substituted or unsubstituted C1-C20arlyalkyl, substituted or unsubstituted C1-C20 alkoxyl, and halogen(such as fluoro, chloro, bromo, or iodo), wherein one or more instancesof R¹, R², R³, and R⁴ are optionally substituted with a groupindependently selected from C1-C20 alkxoyl and halogen (such as fluoro,chloro, bromo, or iodo); and

R⁵ is hydrogen.

In at least one aspect, each instance of R¹, R², R³, and R⁴ of theaniline monomer of Scheme 1 is independently selected from hydrogen andunsubstituted C1-C20 alkyl. In one or more aspects, C1-C20 alkyl isselected from methyl, ethyl, propyl, n-butyl, iso-butyl, sec-butyl,n-pentyl, iso-pentyl, sec-pentyl, n-hexyl, iso-hexyl, and sec-hexyl. Inat least one aspect, each instance of R¹, R², R³, and R⁴ is hydrogen.

Alkyl-substituted aryl sulfonic acids (or solutions thereof, e.g.organic solutions) of the present disclosure can have 1 wt % or less ofunsulfonated hydrocarbon content and can be a dialkyl-substitutednaphthyl sulfonic acid, such as DNNSA. Alkyl-substituted aryl sulfonicacids, such as DNNSA, having 1 wt % or less of unsulfonated hydrocarboncontent can be obtained commercially from King Industries.

In at least one aspect, an alkyl-substituted aryl sulfonic acid (such asDNNSA) (or solution thereof) has a hydrocarbon content of about 1 wt %or less, such as about 0.5 wt % or less, such as about 0.1 wt % or less,such as from about 0.001 wt % to about 1 wt %, such as from about 0.01wt % to about 0.5 wt %, based on the total weight of the acid (the acidabsent additional solvent, e.g. isopropanol).

A molar ratio of alkyl-substituted aryl sulfonic acid:aniline in methodsof the present disclosure can be from about 0.2:1 to about 2:1, such asfrom about 0.3:1 to about 1:1, such as from about 0.8:1 to about 1:0.8,such as about 1:1.

Catalysts of the present disclosure can include any suitable ammonium orsulfate catalyst, such as ammonium persulfate.

Furthermore, addition of additional hydrocarbon solvent might not bepreferred. Addition of high levels of, for example, heptane or hexaneprevents the emulsion from forming. For example, if a method isperformed with only DNNSA in heptane and no 2-butoxyethanol, thereaction might not proceed to yield a soluble product.

Flow Reactor Processes

Processes using alkyl-substituted aryl sulfonic acid (such as DNNSA) toform polyanlines of the present disclosure (also referred to hereinafteras PANI-Acid) as a solvent-soluble polymer by flow reactor chemicalprocessing are disclosed herein. The disclosed system and methodsprovide unique processing sequences for direct collection of thepurified emeraldine salt without post reactor manipulation. The presentsystems and methods provide improvement over known methods ofsynthesizing conductive polymers, and in particular conductive polymersalts, for example, PANI-Acid using very short reaction times nototherwise obtainable using conventional methods, which require longreaction times.

By way of example, the present systems and methods provides improvementin the efficient and controlled synthesis of polyaniline (PANI) salt asa soluble, intrinsically conductive polymer. A continuous flow synthesisof PANI-Acid or an “emeraldine salt” is herein described using a flowreactor. In some examples the flow reactor comprises a microfluidic (1to about 750 um I.D.) tube reactor. In some examples, the microfluidictube comprises a fluoropolymer, e.g., TEFLON®. The tube reactor providesa suitable surface for deposition of the forming polymer and astraightforward purification of the conductive polymer salt.

As used herein, the phrase “flow reactor” is inclusive of a micro-flowreactor. A micro-flow reactor is used herein as a flow reactor havingflow dimensions, e.g., tubing inner diameter (I. D.), less than 1 mm(1000 microns).

As further described below, in some examples as the polymerizationreaction proceeds, the majority of the polymer product deposits on thewalls of the tubing. The polymeric product can be purified by washingwith water to remove aqueous soluble reactants, reagents, and sideproducts.

The conductive polymer salts formed in the flow reactor and deposited onthe walls of the tubing can be eluted with organic solvent to providesoluble conductive polymer salt suitable for solid casting, filmforming, or precipitation. The apparatus is configurable for in-situcharacterization e.g., by UV-Vis spectroscopy, infrared, and/or massspectroscopy.

An apparatus and related methods for polymerizing at least one reactantare described. In certain examples, the apparatus is a microfluidicapparatus comprising a mixing chamber and microchannel. In addition, thereactor can further comprise an output chamber and a detection unit thatis operatively connected to the microchannel.

Any suitable apparatus (e.g., flow reactor) can be used to formpolyanilines of the present disclosure, such as those described in U.S.Pat. No. 10,118,992, which is incorporated by reference herein forpurposes of U.S. law.

With reference to FIG. 1A, flow reactor system 100 shown. First reactant10 (e.g., an aniline) and second reactant 20 (e.g., an alkyl-substitutedaryl sulfonic acid) are introduced to first mixing unit 30. The reactorsystem 100 shown in FIG. 1A can produce conductive polymer salts(mass/per unit time) more efficiently than conventional macroscaledevices or batch reactors. Flow reactor system 100 is capable ofoperating at a range of processing temperatures from room temperature toabout 250° C., such as at process temperatures less than 100° C. In someexamples, ambient temperature is between about 50° F. (10° C.) to about90° F. (32° C.). In some examples reactants 10, 20 are introduced,independently, to the first mixing unit 30 at a predetermined flow rateand/or predetermined concentration such that a desired molar ratio ofreactants 10, 20 are mixed prior to being introduced to the flowreactor. In other examples, reactants 10, 20 are introduced together tothe first mixing unit 30 such that a desired molar ratio of reactants10, 20 are mixed prior to being introduced to the flow reactor. Firstmixing unit 30 can be any suitable mixing device. In some examples, themixing device is a high-speed or ultrahigh speed mixing device capableof emulsifying one or more solutions, for example an aqueous solutionand a non-aqueous solution. In some examples, first reactant 10 iscontained in an aqueous solution and second reactant 20 is contained ina non-aqueous solution, whereas first mixing unit 30 is designed foremulsifying first reactant 10 and second reactant 20. Third reactant 50joins first and second reactants in second mixing unit 60. In someexamples, reactant 50 is a catalyst. After mixing in second mixing unit60, reactants are introduced to tubing 70 via inlet port 65. Tubing 70comprises discharge port 80, which can be monitored by analysisequipment 90. Analysis equipment 90 can include spectroscopic equipmentto interrogate and analyze materials flowing from discharge port 80,such as unreacted materials and/or reaction products. Spectroscopicequipment includes UV-Vis, IR (near-, mid-, and far-IR), and massspectroscopy. Other analytical and interrogating techniques can be used,such as capacitance, pH, etc. Pressure regulating unit 67 can bepositioned at the outlet of flow reactor 70 for monitoring a change inpressure during polymerization or during the collection step ofpolymerized material and information from pressure regulating unit 67can be used by a controller to cease introduction of the reactants(e.g., aniline) to the flow reactor. An additional pressure regulatingunit 67 can also be positioned at the inlet of flow reactor 70 forexample, for monitoring changes in pressure during the process. Fluidlines 69 can be independently fluidically coupled to flow reactor 70 soas to introduce purging media 66 (e.g., water) or collecting medium 68(e.g., solvent) for collecting polymerization product from flow reactorunits 70.

In some examples, flow reactor system 100 has a single inlet port to thetubing 70. In other examples, flow reactor system 100 has additionalinlet ports positioned between inlet port 65 and discharge port 80. Asshown in FIG. 1A, tubing 70 can be coiled around to provide an extendedtubular flow reactor.

In some examples, tubing 70 is contained in housing 40 that providestemperature control and/or support and/or protection from damage of thetubing 70. In some examples, housing 70 has an inside surfacesurrounding at least a portion of the tubing 70 such that the coiledtubing 70 is at least partially contained within the housing 40. In someexamples, housing 40 is configured to provide temperature control to thetubing 70, which includes heating and/or cooling.

As shown in FIG. 1B, alternate flow reactor configuration 100 a is shownwith plurality of tubing 70 a, 70 b arranged in a coil configurationcoupled in series. Tubing 70 a, 70 b can be dimensionally the same orcan have different lengths and/or different inner diameters. In thisconfiguration, the housing can be bifurcated into separate, sections 40a, 40 b receiving tubing 70 a, and 70 b that can be independentlymanipulated for heating and/or cooling the tubing. Alternatively, flowreactor configuration 100 a can have a single housing receiving tubing70 a, 70 b. In contrast to a parallel array configuration of the tubing,where the process stream is split prior to entering the flow reactor,the series array maximizes the amount of time that the reaction mixtureis maintained in a diffusion-limiting condition. While not to be held byany particular theory, it is believed that maintaining the reactionmixture in a diffusion limiting condition provides improvement of thepresently disclosed reactions for producing conductive polymer saltsfrom reactants in emulsion compared to batch processing. The presentmethods and systems disclosed herein provide for such a diffusionlimiting condition for the emulsion of reactants.

With reference to FIG. 1C, an exemplary flow reactor system 100 b isshown. A plurality of flow reactor units 70 c, 70 d, and 70 e, are shownin a parallel flow configuration. Each flow reactor 70 c, 70 d, and 70e, independently, can be isolated via flow control valves 63 situated atthe inlet and outlet of each flow reactor introduction of monomersolution to the corresponding flow reactor. Flow control valves 63 canbe manually operated and/or solenoid-based configured forcomputer-control using conventional controlling devices. Flow controlvalves 63 can contain one or more check valves for preventing backflowof dispersion solution. One or more pressure regulating units 67 can bepositioned at the outlet of one or more of the flow reactors formonitoring a change in pressure during polymerization or during thecollection step of polymerized material. Additional pressure regulatingunits 67 can also be positioned at the inlet of each flow reactor. Flowcontrol valves 63 can be coupled to pressure data from the controller soas to isolate one or more of the flow reactors 70 c, 70 d, and 70 e, foractivating purge and/or polymer recovery. In this configuration, flowreactor system 100 b can be continuously operated by selectivelyisolating one or more flow reactor units 70 c, 70 d, and 70 e forcollecting polymerization product and/or maintenance while maintainingmonomer introduction to one or more of the remaining flow reactor units.Alternatively, flow reactor system 100 b can be semi-continuouslyoperated, for example by temporarily ceasing the introduction of monomerto one or more of the flow reactor units 70 c, 70 d, and 70 e.Additional fluid lines 69 can be independently fluidically coupled toone or more of the flow control valves 63 so as to introduce purgingmedia 66 (e.g., water) or collecting medium 68 (e.g., solvent) forcollecting polymerization product selectively from one or more flowreactor units 70 c, 70 d, and 70 e. One or more of flow reactor units 70c, 70 d, and 70 e can be physically removed from flow reactor system 100b for transport with or without polymerization product recovered from inthe inner diameter of the tubing.

With reference to FIG. 2, process flow 201 is depicted as exemplary ofthe methods disclosed herein. Thus preparing an emulsion of aqueousmonomer and an acid in a non-aqueous solvent is depicted in Block 205.Introducing the emulsion and a catalyst to the micro reactor tubing isdepicted in Block 210. After predetermined time, flow of one or more ofthe reactants can be terminated and optionally, flushing of the microreactor tubing with water can be performed as shown in Block 215. Block215 can be performed so as to remove unreacted reactants and/or lowmolecular weight products. Recovering polymer from the micro reactortubing with organic solvent is performed in Block 220.

With regard to FIGS. 3 and 4, a sectional view of the tubing 300 withinternal surface 310 of tube bore having an internal diameter D. In someexamples, a maximum diameter is less than the diameter at whichadvantages of diffusion-limited reaction diminishes. This maximumdiameter can be as much as 4000 microns, similar to tubing diameter usedfor high pressure tubing. In other examples, optimal results may beobtained using diameters less than 4000 microns, less than 3000 microns,or less than 1000 microns to a minimum diameter of about 100 microns.While not to be held to any particular theory, it is believed thatfaster reaction rates for the reactions disclosed and described hereinoccur with decreasing reactor tubing inner diameter dimensions, as muchas 10⁴ to 10⁶ in microfluidic systems as previously reported with sometrade-off of reaction volume per unit time. In one example, thecapillary to 300 is made of glass, metal, plastic or glass or metal thatis coated on its inner surface with a polymer e.g. a fluoropolymer. Thetubing may be encased in another polymer or be metal coated.

Tubing length can be chosen based on the ability of the selectedcomponents of the system (pump, tubing burst strength, fittings, etc.)to handle pressure. The maximum length of tubing suitable for use withthe presently disclosed system is a function of back-pressure and theability to transport product through the entire length of the tubing. Insome examples, the system can be configured to operate at a tubinglength coupled with a tubing inner diameter such that the systemoperates at or below about 20 bar (280 psi). In some examples, thelength of tubing does not exceed 500 meters with tubing having an innerdiameter of less than 4000 microns. In other examples, the tubing 300 istubing of diameter less than 1000 microns (microfluidic tubing) with alength of about 100 meters or less. Other combinations of tubingdiameter and length can be used commensurate with the operatingparameters of the system and the desired reaction volume per unit time.

The cross-section of the tubing may be any shape, but preferably iscircular. In some examples, polymerization occurs on internal surface310 of tube bore as shown in FIG. 4 where polymerization product 400restricts the internal diameter D to a reduced diameter D′. In someexamples, the tubing inner diameter or the reduction in internaldiameter D is symmetrical about longitudinal axes A-A, B-B. In someexamples, the tubing inner diameter or the reduction in internaldiameter D is non-symmetrical about longitudinal axes A-A, B-B. Thisreduction in diameter D to diameter D′ of the tubing 300 causes a backpressure that can be measured and/or used in part to control the processherein.

This back pressure can be monitored whereas at the beginning ofpolymerization back pressure at time T1 is consistent with the viscosityand flow rate of the emulsified reactant mixture being fed into tubing300. During a time period T2, where polymerization has caused areduction in the internal diameter of tubing 300, the back pressurebegins to increase and approaches a threshold. In some examples, thesystem is designed to terminate polymerization when the back pressurevalue reaches the predetermined threshold. The rate of change of theback pressure as depicted in time period T2 can be adjusted taking intoaccount the burst strength of the capillary tubing and other reactorparameters by manipulation of the viscosity of the reactants, the molarconcentration of the reactants and/or catalyst, temperature, flow ratesand combinations thereof. FIG. 5 depicts a process flow diagram 500 thatrepresents an example of the presently disclosed method. Thus, pumpingreactant emulsion and catalyst into the micro reactor tubing is depictedby Block 505. Monitoring back pressure of the reactant emulsion duringthe polymerization process is depicted in Block 510. Using conventionalpressure monitoring equipment either external or electrical with thepumping devices is envisioned. Introduction of the reactant emulsion isterminated once the threshold back pressure is reached as depicted inBlock 515. Recovering the product polymer from the micro reactor tubingby flushing with organic solvent is depicted in Block 520.

By way of example, the method disclosed herein can be applied to themanufacture a polyaniline of the present disclosure. In at least oneaspect, a polyaniline formed by a method of the present disclosure ispolyaniline-dinonylnaphthalene sulfonic acid salt (“PANI-DNNSA”), whichis a conductive polymer for electronic applications such as organiclight-emitting diodes (OLED), solar cells, semiconductors, displayscreens and chemical sensors.

Thus, and as an exemplary example, a continuous flow synthesis processof PANI-DNNSA salt is provided. The flow apparatus was designed to allowaddition of the oxidative reagent to a preformed emulsion of aqueousaniline and the organic soluble DNNSA. For example, emulsionpolymerization of equimolar amounts of aniline and DNNSA in the presenceof ammonium persulfate as the oxidative catalyst can be performed. Thereaction is depicted below in Scheme 2:

Thus, with reference to FIG. 6, process flow diagram 600 is shown.Blocks 602 and 604 introduce an aqueous composition comprising ananiline and a non-aqueous composition comprising an alkyl-substitutedaryl sulfonic acid, respectively into a first mixer. Forming a reactantemulsion in the first mixer is performed in Block 610. Introducing acatalyst and the reactant emulsion into a second mixer is performed inBlock 615. Introducing to the micro reactor tubing and obtaining athreshold back pressure is performed in Block 620. Terminatingintroduction of reactant emulsion and catalyst to micro reactor tubingis performed in Block 625. Optionally, the micro reactor tubing can beflushed with water in Block 630 to remove unreacted material and/or lowmolecular weight polymer. Recovering polyaniline polymer salt from microreactor tubing with organic solvent is carried out in Block 635.

ASPECTS

The present disclosure provides, among others, the following aspects,each of which may be considered as optionally including any alternateaspects.

Clause 1. A polyaniline having a weight average molecular weight (Mw) offrom about 55,000 g/mol to about 80,000 g/mol, as determined by gelpermeation chromatography, and a molecular weight distribution (Mw/Mn)of from about 1 to about 5, as determined by gel permeationchromatography.Clause 2. The polyaniline of Clause 1, wherein the polyaniline issubstantially free of hydrocarbon content.Clause 3. The polyaniline of Clauses 1 or 2, wherein the polyaniline isan acidified polyaniline having a plurality of conjugate basecounterions.Clause 4. The polyaniline of any of Clauses 1 to 3, wherein thepolyaniline has an Mw of from about 50,000 g/mol to about 150,000 g/mol,as determined by gel permeation chromatography.Clause 5. The polyaniline of any of Clauses 1 to 4, wherein thepolyaniline has an Mw of from about 110,000 g/mol to about 140,000g/mol, as determined by gel permeation chromatography.Clause 6. The polyaniline of any of Clauses 1 to 5, wherein thepolyaniline has a number average molecular weight (Mn) of from about50,000 g/mol to about 100,000 g/mol, as determined by gel permeationchromatography.Clause 7. The polyaniline of any of Clauses 1 to 6, wherein thepolyaniline has an Mn of from about 72,000 g/mol to about 74,000 g/mol.Clause 8. The polyaniline of any of Clauses 1 to 7, wherein thepolyaniline has a molecular weight distribution (Mw/Mn) of from about 1to about 5, as determined by gel permeation chromatography.Clause 9. The polyaniline of any of Clauses 1 to 8, wherein thepolyaniline has an Mw/Mn of from about 1.5 to about 1.9, as determinedby gel permeation chromatography.Clause 10. The polyaniline of any of Clauses 1 to 9, wherein thepolyaniline has a z-average molecular weight (Mz) of from about 100,000g/mol to about 250,000 g/mol, as determined by gel permeationchromatography.Clause 11. The polyaniline of any of Clauses 1 to 10, wherein thepolyaniline has an Mz of from about 152,000 g/mol to about 204,000g/mol.Clause 12. The polyaniline of any of Clauses 1 to 11, wherein thepolyaniline has a peak average molecular weight (Mp) of from about50,000 g/mol to about 150,000 g/mol.Clause 13. The polyaniline of any of Clauses 1 to 12, wherein thepolyaniline has an Mp of from about 113,000 g/mol to about 136,000g/mol.Clause 14. The polyaniline of any of Clauses 1 to 13, wherein thepolyaniline has a thermal stability of about 100° C. or greater.Clause 15. The polyaniline of any of Clauses 1 to 14, wherein thepolyaniline has a thermal stability of from about 150° C. to about 160°C.Clause 16. The polyaniline of any of Clauses 1 to 15, wherein thepolyaniline is represented by Formula (I):

wherein:each instance of R¹, R², R³, and R⁴ is independently selected fromhydrogen, substituted or unsubstituted C1-C20 alkyl, substituted orunsubstituted C1-C20 alkoxyl, and halogen, wherein one or more instancesof R¹, R², R³, and R⁴ are optionally substituted with a groupindependently selected from C1-C20 alkxoyl and halogen;each instance of A⁻ is an anionic ligand; andn is an integer such that the polyaniline has a weight average molecularweight (Mw) of from about 55,000 g/mol to about 80,000 g/mol.Clause 17. The polyaniline of any of Clauses 1 to 16, wherein thepolyaniline has an Mw of from about 65,000 g/mol to about 70,000 g/mol.Clause 18. The polyaniline of any of Clauses 1 to 17, wherein eachinstance of R¹, R², R³, and R⁴ is independently selected from hydrogenand unsubstituted C1-C20 alkyl.Clause 19. The polyaniline of any of Clauses 1 to 18, wherein eachinstance of R¹, R², R³, and R⁴ is hydrogen.Clause 20. The polyaniline of any of Clauses 1 to 19, wherein eachinstance of A− is dinonylnaphthalene sulfonate.Clause 21. A film comprising the polyaniline of any of Clauses 1 to 20,wherein the film has a hydrocarbon content of about 1 wt % or less,based on the total weight of the film.Clause 22. The film of Clause 21, wherein the film has a hydrocarboncontent of about 0.5 wt % or less, based on the total weight of thefilm.Clause 23. The film of Clauses 21 or 22, wherein the hydrocarbon isnaphthalene.Clause 24. The film of any of Clauses 21 to 23, wherein the film has anoutgassing % of about 0.5% or less.Clause 25. The film of any of Clauses 21 to 24, wherein the film has anoutgassing % of about 0.1% or less.Clause 26. A method comprising:

-   -   Introducing an emulsion of an aqueous solution of an aniline and        an organic solvent solution of an alkyl-substituted aryl        sulfonic acid having 1 wt % or less of hydrocarbon content into        a flow reactor, the flow reactor comprising a length of tubing        having an inner diameter; and    -   polymerizing the monomer within the tube to form a polyaniline.        Clause 27. The method of Clause 26, further comprising        introducing a catalyst to the emulsion.        Clause 28. The method of Clauses 26 or 27, further comprising        introducing a catalyst to the flow reactor.        Clause 29. The method of any of Clauses 26 to 28, wherein the        length of tubing is coiled.        Clause 30. The method of any of Clauses 26 to 29, wherein the        flow reactor comprises a plurality of tubing arranged in a        parallel flow configuration.        Clause 31. The method of any of Clauses 26 to 30, wherein the        molar ratio of aniline to acid is from about 1:1 to about 0.2:1.        Clause 32. The method of any of Clauses 26 to 31, wherein the        catalyst is ammonium persulfate.        Clause 33. The method of any of Clauses 26 to 32, wherein the        alky-substituted aryl sulfonic acid is a dinonyl naphthyl        sulfonic acid.        Clause 34. The method of any of Clauses 26 to 33, wherein the        organic solvent solution of alkyl-substituted aryl sulfonic acid        has 0.5 wt % or less of hydrocarbon content.        Clause 35. The method of any of Clauses 26 to 34, wherein the        organic solvent solution of alkyl-substituted aryl sulfonic acid        has 0.1 wt % or less of hydrocarbon content.        Clause 36. The method of any of Clauses 26 to 35, wherein the        organic solvent solution of alkyl-substituted aryl sulfonic acid        has 0.5 wt % or less of naphthalene.        Clause 37. The method of any of Clauses 26 to 36, further        comprising recovering the polyaniline from the tubing.        Clause 38. The method of any of Clauses 26 to 37, wherein the        polyaniline has an Mw of from about 50,000 g/mol to about        150,000 g/mol, as determined by gel permeation chromatography.        Clause 39. The method of any of Clauses 26 to 38, wherein the        polyaniline has an Mw of from about 65,000 g/mol to about 70,000        g/mol, as determined by gel permeation chromatography.        Clause 40. The method of any of Clauses 26 to 39, wherein the        polyaniline has an Mw/Mn of from about 1.5 to about 1.9, as        determined by gel permeation chromatography.        Clause 41. The method of any of Clauses 26 to 40, wherein the        polyaniline has a thermal stability of about 100° C. or greater.        Clause 42. The method of any of Clauses 26 to 42, wherein the        polyaniline has a thermal stability of from about 150° C. to        about 160° C.

Examples

PANI/DNNSA was synthesized using an emulsion polymerization processdeveloped by Kinlen et al., Macromolecules, (1998), 31, 1735-1744. ThePANI/DNNSA(pur) synthesis was performed using 5 purified Nacure samples(C,D,E,F,H) obtained from King Industries. For conductivity measurementsall samples were spun coated on glass at 2000 rpms and heated at 70° C.for 1 hour. All film thickness measurements were performed using aBruker Contour GT-K1 white light interferometer. All films were cast onglass substrates using silver ink as contact points unless otherwisenoted. Resistance was measured using a Keithley SemiconductorCharacterization System with a voltage sweep from −10V to 10V.

Materials

All chemicals where used as is without further purification. PurifiedDNNSA in 2-butoxy ethanol (Nacure 1051) was obtained from KingIndustries. Aniline, ammonium persulfate and xylenes were obtained fromSigma-Aldrich. NMP was obtained from Fisher Scientific. All materialsused were reagent grade.

Methods

PANI/DNNSA Purified DNNSA Batches

For PANI/DNNSA_((pur)), all batches were synthesized following the sameprocedure in a batch reactor. Nacure was purified using ion exchangeresin (Dowex, strongly basic anion exchanger). Purified Nacure (82.926g, 0.09 mol) and water (200 ml) were added to a 500 ml reaction flask.The mixture was cooled to 0° C. (T_(j)). After 60 min, aniline (5.59 g,0.06 mol) was added to the mixture. After 10 min, ammonium persulfate(16.885 g, 0.074 mol) in water (50 ml) was added dropwise over 30 min.Once the reaction was complete, toluene was added to the product and thematerial was washed with 0.01M H2504 (1×) and water (3×). The materialwas rotovapped (3×) to ensure all water was removed. A summary of allreactions can be seen below in Table 1. The conductivity and molecularweight can be seen in Table 2.

TABLE 1 All purified batches of PANI/DNNSA APS (g) Nacure Nacure Anilinein 50 ml Water PANI/DNNSA Lot (g) (g) H20 (g) Ha/An Batch 1 C 82.9265.590 16.900 200.875 1.5 Batch 2 D 82.921 5.585 16.960 200.215 1.5 Batch3 E 82.918 5.586 16.910 200.010 1.5 Batch 4 F 82.926 5.585 16.910200.027 1.5 Batch 5 H 82.926 5.585 16.750 200.083 1.5 Control 105182.963 5.622 16.940 199.784 1.5 Batch 6 D 100.059 5.589 16.930 199.8871.9

TABLE 2 Film conductivity and molecular weight Neat Film IPA TreatedNacure Conductivity Conductivity Mn PANI/DNNSA Lot (S/cm) (S/cm) (kDa)PDI Batch 1 C N/A N/A N/A N/A Batch 2 D N/A 3.31 × 10⁻⁷ N/A N/A Batch 3E 2.09 × 10⁻⁶ 4.96 × 10⁻¹ 34.5 1.6 Batch 4 F 2.86 × 10⁻⁶ 4.39 × 10⁻¹44.4 1.8 Batch 5 H N/A 2.79 × 10⁻⁸ 26.3 1.9 Control 1051 5.89 × 10⁻⁶ 637.4 1.9

Thermal Stability of Neat Films

Thermal stability tests of neat PANI samples from Boron Molecular wereperformed. The samples were spun cast on glass and the resistance wasmeasured. The samples were placed in an oven at 70° C., 100° C. and 130°C. for approximately 24 hrs at each temperature. After the samples wereremoved, they were allowed to cool to room temperature before theresistance measurements were made. A second resistance measurement wasmade after 1 hour at room temperature to ensure no additional changesbefore putting the samples back in at temperature for 24 hours.

Molecular Weight Characterization

Method:

Gel Permeation Chromatography (GPC) was employed to characterize themolecular weight of polyanilines (PANI). 0.02 M ammonium formate (AF) inN-methylpyrrolidinone (NMP) was used as the mobile phase. The universalcalibration technique was used to measure molecular weight distributionsutilizing viscometric and refractive index detectors. All solutions werefiltered through a 0.45 micro filter prior to use. PANI samples wereprecipitated in spectroquality methanol, washed four times with methanoland recovered using vacuum filtration. The samples were air dried,dissolved in AF-NMP, and passed through a 0.2 micron filter directlyinto GPC vials for analysis. The conventional molecular weight (IR MW)were determined by combining universal calibration relationship with thecolumn calibration which is performed with a series of monodispersedpolystyrene (PS) standards.

Batch Process Comparisons:

Nacure and Kpure 1.5:1.0 dopant to aniline ratio. FIG. 7A is a graphillustrating gel permeation results (refractive index vs. retentionvolume (mL)) using a refractive index detector of polyanilines producedusing a conventional DNNSA (line 700) or a DNNSA having less than 1 wt %hydrocarbon content (line 702). The Y-axis is millivolts. FIG. 7B is agraph illustrating gel permeation results (viscometer differentialpressure vs. retention volume (mL)) using a viscometer of polyanilinesproduced using a conventional DNNSA (line 704) or a DNNSA having lessthan 1 wt % hydrocarbon content (line 706). The Y-axis is millivolts.

Results Using Universal Calibration

TABLE 3 NACURE (MAF 2-125) Mn - (Daltons) 73,951 Mw - (Daltons) 121,798Mz - (Daltons) 166,290 Mp - (Daltons) 117,831 Mw/Mn 1.647 KPURE (PANIKPURE) Mn - (Daltons) 72,478 Mw - (Daltons) 138,026 Mz - (Daltons)204,057 Mp - (Daltons) 135,631 Mw/Mn 1.904

Thermal Stability Data

Procedure: Samples of PANI spin coated onto microscope slides and driedat 70° C. Silver bars painted on edges for electrical contacts. Samplesexposed to 25° C., 70° C., 100° C., 130° C., 160° C. and 190° C. fortwenty four hours in a convection oven. Resistance measured for eachexposure. FIG. 8 is a graph illustrating thermal stability data(resistance vs. temperature) of polyanilines, according to one or moreembodiments. Lot F series (Lot F1.54, Lot F1.62, Lot F1.81, MAF Lot F)is samples having samples formed using purified DNNSA. 1801, 1802, 1803,and 1804 are samples formed using unpurified NACURE.

FIG. 9 is a graph illustrating thermal stability data (resistance vs.temperature) of polyanilines, according to one or more embodiments.Lines 1702, 1703, 1704, and MAF-2-125-1 are samples formed usingunpurified NACURE. 1702, 1703, and 1704 samples were formed using a flowprocess. MAF-2-125-1 was formed using a batch process.

TABLE 4 Lot F Lot F Lot F MAF Temperature (° C.) 1.54 1.62 1.81 Lot F1801 1802 1803 1804 25 1.71E+09 2.04E+09 1.30E+09 3.75E+08 1.04E+088.05E+08 1.00E+10 2.39E+09 70 1.34E+09 1.38E+09 4.76E+08 3.83E+081.50E+08 7.48E+08 4.63E+09 1.60E+09 100 4.01E+05 2.35E+07 2.52E+061.07E+07 4.84E+07 5.92E+07 6.76E+07 4.14E+07 130 4.62E+06 2.30E+061.20E+06 1.07E+07 6.36E+07 3.84E+07 4.66E+07 2.97E+07 160 Broke 3.83E+072.80E+07 2.39E+10 3.11E+10 1.30E+10 1.83E+09 4.36E+09 190 Broke 4.02E+112.89E+11 4.68E+11 3.53E+11 3.46E+11 4.89E+11 3.91E+11FTIR SpectraNacure 1051 vs. KPURE CXC 1304

Sample Preparation:

Coat microscope slides. Drop cast: NACURE 1051; KPURE CXC 1304. Washedwith copious amounts of DI water undertap. Slides were dried for 1 hourat 70° C. FTIR Spectra were run on above samples plus neat NACURE andKPURE. FIG. 10a is overlaid FTIR spectra of DNNSA, according to one ormore aspects. KPURE (line 1000) showed no detected water insolubleresiduals. Neat KPURE is shown at line 1002. FIG. 10b is overlaid FTIRspectra of DNNSA, according to one or more aspects. NACURE 1051 (line1004) showed no detected water insoluble residuals. Neat NACURE 1051 isshown at line 1006.

Conclusions:

NACURE leaves behind a very tacky water insoluble residue. Tackymaterial believed to be un-sulfonated aromatic hydrocarbon. Residue isan un-desired impurity. KPURE leaves no residue, an indication that allof the hydrocarbon is completely sulfonated. Supports low outgassingresults under high vacuum.

OutGassing of PANI-DNNSA with Purified DNNSA (F):

% PANI/ Total Condensed Source of DNNSA Mass Lost Volatiles Sample PANIin film (1% max) (0.1% max) EAB-II-100-4 Other Flow 6.4% 1.25% 0.20%EAB-II-104-1 StL Batch  5% 1.92% 0.21% EAB-III-83-1 Boron Flow 4.5%1.37% 0.18% EAB-III-83-2 Boron Flow 4.5% 1.30% 0.19% EAB-III-111 StLBatch* 9.0% 1.94% 0.06% EAB-III-127-4 Stl Batch* 4.5% 1.16% 0.05% BaseResin None  0% 1.11% 0.07% with PANI/DNNSA *Made using KPURE.

Overall, the present disclosure provides polyanilines and methods offorming polyanilines. Polyanilines of the present disclosure can besubstantially free of byproducts such as un-sulfonated hydrocarbonswhich provides reduced “outgassing” of the polyanilines as compared toconventional polyanilines. Reduced outgassing and improved molecularweight properties of polyanilines of the present disclosure provideimproved thermal stability, as compared to conventional polyanilines.Methods of the present disclosure include forming polyanilines by usingan aniline and an alkyl-substituted aryl sulfonic acid (such asdinonylnaphthylenesulfonic acid (DNNSA)). The alkyl-substituted arylsulfonic acid of methods of the present disclosure can have 1 wt % orless of un-sulfonated hydrocarbon content. Use of, for example, DNNSAhaving 1 wt % or less of unsulfonated hydrocarbon content can providepolyanilines having reduced outgassing and improved thermal stability.

While the foregoing is directed to examples of the present disclosure,other and further examples of the present disclosure may be devisedwithout departing from the basic scope thereof. Furthermore, while theforegoing is directed to methods as applied to vehicle components, e.g.of the aerospace industry, examples of the present disclosure may bedirected to other applications not associated with an aircraft, such asapplications in the automotive industry, marine industry, energyindustry, wind turbines, satellites, and the like.

The descriptions of the various examples of the present disclosure havebeen presented for purposes of illustration, but are not intended to beexhaustive or limited to the examples disclosed. Many modifications andvariations will be apparent to those of ordinary skill in the artwithout departing from the scope and spirit of the described examples.The terminology used herein was chosen to best explain the principles ofthe examples, the practical application or technical improvement overtechnologies found in the marketplace, or to enable others of ordinaryskill in the art to understand the examples disclosed herein. While theforegoing is directed to examples of the present disclosure, other andfurther examples of the present disclosure may be devised withoutdeparting from the basic scope thereof.

What is claimed is:
 1. A polyaniline having: a thermal stability ofabout 100° C. or greater, a weight average molecular weight (Mw) of fromabout 50,000 g/mol to about 150,000 g/mol, as determined by gelpermeation chromatography, and a molecular weight distribution (Mw/Mn)of from about 1 to about 5, as determined by gel permeationchromatography.
 2. The polyaniline of claim 1, wherein the polyanilineis substantially free of hydrocarbon content.
 3. The polyaniline ofclaim 1, wherein the polyaniline is an acidified polyaniline having aplurality of conjugate base counterions.
 4. The polyaniline of claim 1,wherein the polyaniline has an Mw of from about 75,000 g/mol to about100,000 g/mol, as determined by gel permeation chromatography.
 5. Thepolyaniline of claim 1, wherein the polyaniline has an Mw of from about110,000 g/mol to about 140,000 g/mol, as determined by gel permeationchromatography.
 6. The polyaniline of claim 1, wherein the polyanilinehas a number average molecular weight (Mn) of from about 50,000 g/mol toabout 100,000 g/mol, as determined by gel permeation chromatography. 7.The polyaniline of claim 6, wherein the polyaniline has an Mn of fromabout 72,000 g/mol to about 74,000 g/mol.
 8. The polyaniline of claim 1,wherein the polyaniline has a molecular weight distribution (Mw/Mn) offrom about 1 to about 3, as determined by gel permeation chromatography.9. The polyaniline of claim 8, wherein the polyaniline has an Mw/Mn offrom about 1.5 to about 1.9, as determined by gel permeationchromatography.
 10. The polyaniline of claim 1, wherein the polyanilinehas a z-average molecular weight (Mz) of from about 100,000 g/mol toabout 250,000 g/mol, as determined by gel permeation chromatography. 11.The polyaniline of claim 10, wherein the polyaniline has an Mz of fromabout 152,000 g/mol to about 204,000 g/mol.
 12. The polyaniline of claim11, wherein the polyaniline has a peak average molecular weight (Mp) offrom about 50,000 g/mol to about 150,000 g/mol.
 13. The polyaniline ofclaim 12, wherein the polyaniline has an Mp of from about 113,000 g/molto about 136,000 g/mol.
 14. The polyaniline of claim 1, wherein thepolyaniline has a thermal stability of from about 150° C. to about 160°C.
 15. The polyaniline of claim 1, wherein the polyaniline isrepresented by Formula (I):

wherein: each instance of R¹, R², R³, and R⁴ is independently selectedfrom hydrogen, substituted or unsubstituted C1-C20 alkyl, substituted orunsubstituted C1-C20 aryl, substituted or unsubstituted C1-C20 alkaryl,substituted or unsubstituted C1-C20 arlyalkyl, substituted orunsubstituted C1-C20 alkoxyl, and halogen, wherein one or more instancesof R¹, R², R³, and R⁴ are optionally substituted with a groupindependently selected from C1-C20 alkxoyl and halogen; each instance ofA⁻ is an anionic ligand; and n is an integer such that the polyanilinehas a weight average molecular weight (Mw) of from about 55,000 g/mol toabout 80,000 g/mol.
 16. The polyaniline of claim 15, wherein eachinstance of A− is dinonylnaphthalene sulfonate.
 17. A film comprisingthe polyaniline of claim 1, wherein the film has a hydrocarbon contentof about 1 wt % or less, based on the total weight of the film.
 18. Thefilm of claim 17, wherein the film has a hydrocarbon content of about0.5 wt % or less, based on the total weight of the film.
 19. The film ofclaim 18, wherein the film comprises about 0.5 wt % or less ofnaphthalene, based on the total weight of the film.
 20. The film ofclaim 20, wherein the film has an outgassing % of about 0.5% or less.